The increasing demand for lower power consumption and environmentally friendly consumer devices has resulted in interest in power supply circuits with “green” technology. For example, on average, a notebook power adapter continuously “plugged in” spends 67% of its time in idle mode. Even with a power adapter which conforms to the regulatory requirement of dissipating less than 0.5 watts/hour, this extended idle time adds up to 3000 watt-hours of wasted energy each year per adapter. When calculating the wasted energy of the numerous idle power adapters, the power lost is considerable. In addition to power adapters, numerous electronic devices spend a substantial amount of time plugged-in but not operating. An opportunity exists for reducing the power lost by these electronic devices.